Danny Fenton Posted October 31, 2010 Author Share Posted October 31, 2010 Hi Thomas and thatnks for all the information, it is much appreciated. The ML7 has now arrived and it will take me a little while to figure out what evrything does. Most of it is fairly obvious. I did turn the head of a bolt until it was cylindrical, using the one tool the previous owner left me. When the crossfeed was fed all the way to the centre of the work the little raised dimple vanished so it was centred. The surface finish was not great, perhaps the tool was not sharp though it looked it? anyway even tried a little 3 in 1 to lubricate the cut. This improved things but not much. Lots of experimenting needed I think. My leading question at the moment is where should I buy tooling from and how will I know what is good and what is rubbish? I don't mind paying for the right stuff innitially so that I know its not me causing problems by using cheap tooling. Unfortunately the four jaw chuck is missing the key, so I will have to measure the hole and try ebay for a key. The 3 jaw is a nearly new Pratt and Bernard, which looks in excellent quality. the 4 jaw has no manufacturers name but looks in very good condition, apart from the missing key. I would like to try milling, so need the four jaw operationsal, I did get a vertical slide so that will help, and I need some milling bits, again any suggestions where is safe to purchase from? Sorry for all the questions..... Quote Link to comment Share on other sites More sharing options...
kc Posted October 31, 2010 Share Posted October 31, 2010 I would say a trip to the Model Engineer Exhibition would answer lots of questions and give any number of suppliers with best prices. Also the secondhand stalls will surely have a chuck key to your measurements or oversize to file down.A digital caliper is very handy and so cheap. Check out digital readouts at the ME too. One thing which is too obvious to say but I will .....if you measure the work with your digital caliper etc and find it is say 5 thou over it is easy to set the dial and cut off 5 thou, only to find it is undersize! Dont ask me how I know this..... ( difference between diameter and radius )A zeroing dial for the ML7 is avail and might be worth buying. Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 31, 2010 Author Share Posted October 31, 2010 Hi kc, thanks for that. I can source all the items I need over the net, however what I need to know is what is good and what is rubbish. There are brands that mean quality and that is the information I am after. I know that the three jaw chuck is top notch, and also the vertical slide. As nice as it would be to go to the ME exhibition its a long way and would be costly just to be sold whatever that retailer wants you to buy. I would rather buy something recomended than learn the hard way. And TBH I trust you guys that have been doing this for years over a trader that may have less than perfect motives. More research needed I guess. I have Micrometers, digital calipers, magnetic stands etc so have a little bit of a head start..... Cheers Danny Quote Link to comment Share on other sites More sharing options...
kc Posted October 31, 2010 Share Posted October 31, 2010 Well I was thinking that the advice from the elders on the SMEE stand would be a help in choosing tools from those on sale. There is also a Northern ME exhibition sometime. Also one of the suppliers of secondhand tools is in Bramcote, Warwickshire. You can visit by appointment. Pretty certain to get your chuck key there and much else. When I went there years ago he had barns full of lathes and every conceivable item all s/h. I think its called Engineers Emporium ( I might be wrong ) but its the only one in Bramcote There are others in the Midlands and North. Some speciallise in cutters, good makes but used etc. Most of the s/h tool traders seem to be from an engineering background and I would trust their advice because they are not really salesmen!I would say the origin of the tools tells you the quality, British is best, German usually good but avoid anything from India or Taiwan, be cautious about China. Some of the the suppliers such as Tracy Tools sell British taps.dies drills and some milling cutters at low prices. People such as Chronos sell a big range of stuff but some turns out to be made in India......... Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted October 31, 2010 Share Posted October 31, 2010 DannyMore than almost anything else learn how to sharpen your tools correctly and keep them that way. This means you need to learn about rake and clearance angles for the various type of tool and the material they are going to be used on. On a second hand ML7 I would avoid carbide tipped tools at least to start with, Yes they will cut almost anything but their geometry requires both power and rigidity. A sharp correctly formed HSS tool will do the job just as well but requiring less of both. Lastly remember the bed sildes are not protected so try to keep the swarf away - I use bits of newspaper cut to fit and held in place with small magnets. Get into the habit of cleaning and oiling all the bare metal surfaces at the end of each session. Well looked after these lathes will last a lifetime. I use my dads 3/1/2" Drummond (about the same size) and he bought that second hand in 1932! Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 31, 2010 Author Share Posted October 31, 2010 Hi kc and Simon, all good advice. I am cleaning and oiling after each use don't worry. I dismantled the crossfeed and removed a great deal of backlash using advice from a thread on RCGroups. I looked at the Chronos website as I have used them before for things like pin vices etc. As you say the quality is variable. But they certainly list lots of goodies. The Myford manual and the Amatuer Lathe Owners book give great detail on sharpening tools and it is a skill I will have to learn quickly. I was intending to stick with HSS tools. The problem will be knowing the pedigree of parts, its all very well avoiding non British made if you can ascertain that fact It is difficult for a novice like me to recognise rubbish, I suppose I was hoping somebody would recomend a brand or supplier that I could trust. I guess that was always going to be too easy. I have ordered some stuff from RDG this morning, just centre drills, a numbered drill set, and the missing 1/4" chuck key. I guess I will see what their stuff is like. I would like a tool post and am tempted to go to Myford directly as I know that will be of good quality. The thing that must be remembered here is this is to aid my modelling, and mustn't become another hobby. I will only be cutting aluminium with the odd bit of steel bar for retract bits. Anyway thanks again for all your advice Cheers Danny Quote Link to comment Share on other sites More sharing options...
thomas oliver 1 Posted November 2, 2010 Share Posted November 2, 2010 Danny, As you intend to try to produce things like retracts then you will need to produce both accuracy and a good finish on parts. You will find that normal mild steel or allow rod is one or two thousandths of an inch down on the nominal size. Silver steel which can be obtained in 13" lengths is accurately ground dead to size and will give good fits in reamed holes. Normal rod plus drilled holes will give lousy results and slop. You will need to investigate, as suggested, the proper top rake, side rake and front clearance angles for the metal you are using. There are lots of sources on the net for this. Alloy requires higher angles than mild steel. It also is prone to give a "built up edge" which destroys the finish. Use Paraffin or pure turps as a lubricant. If I was starting all over I would take the trouble to make an adjustable tool rest for the grinder. A diamond honing wheel of will improve cutting edges a lot and improve finish. You will find that if you have purchased a full set of number drills, 14 of these have no use whatsoever for tapping clearance or interfer is obliteratence fits. Signing off before this text is obliterated, Tom Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 2, 2010 Author Share Posted November 2, 2010 Thanks Thomas, I think one of the first things I will have to make is a decent tool rest for my grinder. I will get some tools and practice grinding tools trying them on alloy as I go. Thanks for the advice on silver steel, I will try and source some. Thanks again evrybody for there time and patience with me over this. Cheers Danny Quote Link to comment Share on other sites More sharing options...
thomas oliver 1 Posted November 2, 2010 Share Posted November 2, 2010 Danny, Sorry about the text c--up at the end of post. You will find good information on lathe work on the Yahoo Boxford site under "Files". There should be extracts from the Boxford handbook on tool angles which is very good as a guide. One method of obtaining a good finish which I use to good effect is to reduce the "Plan trail angle" by turning the toolpost. This is the clearance angle between the work and the cutting edge when looking vertically down. The larger this is the lousier the finish. The smaller it is, the better the finish. You see a lot of advocacy for using round nose tools for finish. This may be OK on large work, where a corner fillet is of little consequence, but for model work, sharp corners are usually the order of the day. When working on very small diameters, you will find that the metal springs away due to flexibility. I made myself a very small rotary tailstock centre many years ago and it is extremely useful for obviating this. They can now be obtained from RDG at reasonable cost I have used tools ground for mild steel on brass for donkeys years to good effect. They cut cleaner and give a better finish than the no back rake tools usually advocated. I have never found them to snatch. It also means you do not have to grind up two sets of tools. If you want to spend more time on the modelling as less on machining, then it is possible to save time with the right equipment. Tom Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted November 2, 2010 Share Posted November 2, 2010 I just have to throw a wobbly in here (as is my wont) Fifteen years ago I got a job on a Norwegian oilrig called Petrolia with a lathe on board made in Russia . No-one on board knew how to use it ,so I was roped in to make various components for drilling etc .The chuck was about 4 ft in diameter ,it had all the usual facilities eg screw threading on a large scale to say the least . I just have to smile to myself when I think of the size of the cutting tools and the flow of tool lubricant required compared with a Myford .Getting grumpy and reminiscing yet again .Sorry, but I must live up to my self- inflicted reputation . Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted November 2, 2010 Share Posted November 2, 2010 As most of the serious stuff has been done - and picking up on Myron's theme - we recently took delivery of a new low temperature grinding machine. These are quite unusual and this one is destined purely for research purposes. It was built especially for us by some colleagues in Georgia (the one in the former USSR, not the USA). Anyway after many adventures about delivery it finally arrived. We prepared to commission it. Imagine our surpise when we removed the cover on the control box to find that every single wire in there was green! BEB Quote Link to comment Share on other sites More sharing options...
Phil Claridge Posted November 3, 2010 Share Posted November 3, 2010 must be the eco friendly version beb Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted November 3, 2010 Share Posted November 3, 2010 Posted by Phil Claridge on 03/11/2010 08:50:36: must be the eco friendly version beb LOL Apparently there is some obscure European standard that says you do not have to colour code wires - you can instead simply number them. Seems a bit daft to me - asking for trouble. When dealing with 415V 3-phase I like to be really sure which wire is which! Anyway our H&S people will have none of it - so we having to rewire the whole cabinet. BEB Quote Link to comment Share on other sites More sharing options...
Phil Claridge Posted November 3, 2010 Share Posted November 3, 2010 mr cameron wont like you doing that beb Quote Link to comment Share on other sites More sharing options...
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